ISO/TC 131/SC 7/WG 3 - Design criteria for standard O-ring applications

ISO 3601-2:2016 specifies the housing (gland) dimensions for class A O-rings for general industrial applications conforming to ISO 3601-1, as well as housing dimensions for class B O-rings used on selected metric-dimensioned hardware, e.g. fluid power cylinder bores and piston rods. These O-rings are for use in general hydraulic and pneumatic applications without and with anti-extrusion rings (back-up rings). The dimensions of the O-rings (d1 and d2), size codes (SC) and tolerances conform to ISO 3601-1. Housing dimensions for the O-rings intended for aerospace applications that are specified in ISO 3601-1 are addressed in Annex A.

ISO 3601-5:2015 contains the material specification of a selection of standard elastomeric materials (rubber) for O-rings used in general industrial applications. It also indicates the ability of the materials to satisfy many of the requirements associated with fluid power components. Only materials which are in universal usage are specified; other compounds are available and can be used. The required physical properties and test methods (including test specimen) should be agreed upon between equipment manufacturer/user and O-ring manufacturer/supplier.

ISO 3601-1:2012 specifies the inside diameters, cross-sections, tolerances and designation codes for O-rings used in fluid power systems for general industrial and aerospace applications. The dimensions and tolerances specified in ISO 3601-1:2012 are suitable for any elastomeric material, provided that suitable tooling is available.

ISO 3601-3:2005 lays down the quality acceptance criteria of O-rings used in fluid systems, the dimensions of which are standardized in ISO 3601-1, ISO 16031-1 and ISO 16031-2. ISO 3601-3:20051 also defines and classifies surface imperfections on O-rings and specifies maximum acceptable limits for these imperfections. ISO 3601-3:2005 is also applicable to O-rings to be used in aerospace construction.

ISO 3601-1:2008 specifies the inside diameters, cross-sections, tolerances and designation codes for O-rings used in fluid power systems for general industrial and aerospace applications. The dimensions and tolerances specified in ISO 3601-1:2008 are suitable for any elastomeric material, provided that suitable tooling is available.

ISO 3601-1 specifies the inside diameters, cross-sections, tolerances and size identification code for O-rings used in fluid power systems for general purpose applications (series G), as well as for aerospace and similar applications (series A). The dimensions and tolerances specified in ISO 3601-1 are suitable for any elastomeric material, provided that suitable tooling is available.

ISO 3601-5 evaluates the suitability of a number of elastomeric materials (rubber) which may be used for O-rings in industrial applications. It also indicates the ability of the materials to satisfy many of the requirements associated with fluid power components and systems and includes temperatures and fluid compatibility. Only materials which are in universal usage are specified, other compounds are available and can be specified.

The dimensions and tolerances specified in this part of ISO 3601 are suitable for any elastomeric material provided the suitable tooling is available. The figure shows the typical O-ring configuration. Table 2 contains the series G (general purpose applications), and table 3 the series A (aerospace applications). This second edition cancels and replaces the first edition (1978).

This part of ISO 3601 defines and classifies surface imperfections on O-rings and specifies maximum acceptable limits for these imperfections, and it is also applicable to O-rings to be used in aerospace construction. Gives quality grades and definitions, and the table contains categories of surface imperfections together with schematic illustrations of these imperfections. An annex gives examples of surface imperfections (figures 1 to 8).